I have a 2000 Mercury Grand Marquis 4.6L V8 with 173,000 miles which I bought last July. Recently I did the oil change for the first time and put in the Ford recommended 5W20. I noticed afterwards that when I cold start the car in below freezing temperatures I get a clacketing noise which disappear once the engine warms up. Could it be the timing chain making the noise, or do the valves need adjusting? I am guessing the dealer I got the car from put in a thicker weight oil to hide the noise. Should I just put in a thicker oil when I do my next oil change?
Timing chain is usually more of a rattling noise, clacking might be valve lifters or even the beginning of a rod knock. Maybe post a video demonstrating the noise if possible.
The valve lifters are hydraulic, there is no adjustment, however it is certainly possible that lifters are worn or clogged. I would not put oil in the engine any heavier than what the manufacturer recommends.
Would any of those conditions explain why the noise disappears once the engine warms up? As for the oil, initially Ford recommended 5W30 but a few years back they came up with a service bulletin and changed the recommended oil to 5W20. I'm guessing the car ran for the first 20+ years on 5w30. The noise only appeared after I did the oil change, and only comes when the engine is cold.
Would any of those conditions explain why the noise disappears once the engine warms up?
Yes.
Did you put the right amount in? 5W-20 and 5W-30 aren't that much different, unless somebody did it consistently over 100k miles or more. They usually last a longer time, compared to more modern Fords. Might just need cleaned with Scotty's cleaner. I can never remember what it's called.
Yeah, that's what I was thinking about, lol. Thanks
Yes I put the right amount of oil in. I have driven about 1000 miles since the oil change and the oil still looks relatively clean and the engine isn't burning oil. I will try the easiest thing first and try out the carbon clean and see what happens.